Avoid deleting and creating connections, which is really a rather rare
event anyway, and simply remember the connection object and reuse it
when a new one is requested.
The NetworkManager usage was mostly for low connection counts and this
made defaults selection easy.
With more usages it is important to allow the NWM-connection to be more
configurable about memory usage and leaner in general.
This changes the headers-buffers (used to create envelopes) to not be per
connection anymore but per thread using the tread_local keyword.
This changes the ring-buffers to become configurable using
NetworkConnections::setMessageQueueSizes().
Also removing some include statements where they were not really needed
in the P2PNet lib.
Allow user to shutdown a connection, making it instantly invalid.
Allow user to register a callback for errors.
And fix pinging to be disabled on legacyP2P style connections.
Move some globals and all stuff pulling in crypto to the
server/serverutil.cpp file
Remove dead code.
Move several items that were used in only one place to the respective
files using them.
Move the class WaitUntilFinishedHelper into its own file.
Made sure no header includes utils.h
remove a handfull of files including utils.h for nothing.
This adds all the header ints to chunked messages, solving the problem
of losing RequestId on roundtrips if the answer was too big.
Added a unit test for this "new" features.
This makes callbacks all use shared_from_this() in order to avoid
callbacks being done on deleted instances (thanks boost!).
Last, special case when the user doesn't connect but just sends messages
which caused a send of data, only to realize the connection wasn't open,
and then a connect.
This makes sure we immediately start a connect on queue of a message.
I added some docs to bind() that handlers there should call
accept().
Also made sure that when nobody accepts a connection it actually
gets disconnected instead of just being ignored.
Make sure that a NetworkConnection object (which owns the callbacks)
doesn't return from its destructor until the already scheduled callbacks
in another thread have been completed.
This avoids shutdown scenarios where we execute in a deleted
object.